2002 Southwest Idaho Winter and Spring Small Grain Variety Performance
The 2002 season marked the 18th season of the Southwestern Idaho Cooperative Extension Winter and Spring Small Grain Performance Trials. The trials, supported by the Idaho Wheat Commission and Idaho Barley Commission, enable the testing of public and private varieties and advanced lines under the irrigated and dryland conditions of the Treasure Valley. The season was characterized by a cool and wet fall , a mild winter, a cool early spring and then above normal temperatures during grain filling, especially for spring plantings. Cool temperatures in late fall and early spring would reduce tillering of fall planted trials and delay maturity. Delayed maturity caused grain filling to occur under the warmer conditions that effectively reduced the duration of grain fill. Reduced grain filling reduced both yields and test weight.
Winter Trials
Four irrigated winter wheat trials were conducted during the 2002 season. Two of the trials were planted in mid October (Parma R &E Center early on Oct 10 and Weiser early October 15) and two in mid November (Parma R& E Center late November 12 and Hammett late November 14) to evaluate variety performance under both early and late planting conditions.
The early planted trials were the most productive.
Production in both Parma trials was adversely affected by high winds and hail that caused extensive lodging. Soft white winter wheat protein values averaged high for both Parma early (11.9%) and Hammett late (11.7%) indicating that excessive N was available for these sites. Excessive N alone can limit production een in the absence of lodging. Protein at Parma late (9.5%) suggested N may have been slightly limiting to production and that was especially true for the Weiser trial where protein (8.4%) averaged very low. Production at Weiser was possibly limited by moisture stress as indicated by plant height which averaged only 35". Production for the late planted trial at Parma was reduced also from the late planting and may also have been limited in N based on the protein which averaged less than 10%.One dryland site was planted October 25 near Midvale.
Spring Trials
Three irrigated spring trials were planted at Parma on March 5, Weiser on March 20, and Kuna on March 18. Parma averaged low in low protein (9.2% for soft white springs) and was likely limited in available N. Production was above average at Parma despite a stressful grain filling environment. Moisture stress at Kuna reduced plant height and yield and the high protein for the soft whites (13.3%) suggested that available N may also have been excessive. Yields were lowest at Weiser where protein for soft whites also was high (12.9%). Spring barley was evaluated at only two locations (Parma and Kuna) due to reduced funding from the Idaho Barley Commission. Yields were considerably higher at Weiser that at Parma as were the test weights. We can not explain the high test weights at Weiser in such a stressul year. Yields at Parma were likely reduced from the lodging and shattering associated with high wind and hail in mid July.
2002 Individual Site Performance